Sewing-machine slack-thread controller.



1. D. KARLE. SEWING MACHINE SLACK THREAD CONTROLLER.

APPLICATION FILED MAR. 30. l9lb- Patented Dec. 26,1916.

w i- 1! v 4 TTORNEY WITNESSES.

fa? M M H m w m m M m m m UNITED STATES PATENT OFFICE.

JOHN D. RAB-LE,

OF BOSELLE PARK, NEW JERSEY, ASSIGNOR TO THE SINGER MANU- FACTURING COMPANY, A CORPORATION OF, NEW JERSEY.

SEWING-MACHINE SLACK-THREAD CONTROLLER.

Specification Letter: ratent.

Patented Dec. 26, 1916.

To all whom it may concern:

Be it known that I, J 01m D. KARLE, a citizen of the United States, residing at Roselle Park, in the county of Union and State of New Jersey, have invented certain new and useful Improvements in Sewing-Machine Slack-Thread Controllers, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention has for its object to provide a simple, effective and inexpensively constructed slack-t1 tread controllin device for use in connection wii'. hrea -tension device.

According to the px esent improvement, in its preferred embodiment, the tension-stud is secured for circular adjustment inabushing riveted within a suitable aperture of a sheet -metal face-plate which is formed with concentric apertures to receive prongs or r vets at one end of a sheet-metal casing surrounding said bushing and referably provided with a lateral 00p a ording a socket to receve the thread-guard pin over which the thread is led from between the tension-disks sustained b the stud. The tension-stud is surrounde by a s ring having one end attached thereto an rovided at the opposite end with a latera threadarm resting normally against the shoulder of a tubular stopmember which is fitted to the cylindrical inner wall of the casing to which it is secured b a clamp-screw in circularly adjustable re ation.

In the accompanying drawings, Figure l is a sectional plan of a sewing machine faceplate provided with a tension device and a slack-thread controller embodying the present improvements. Fig. 2 is a front end view and Fig. 8 a rear end view of the sheetmetal casing and the parts contained therein. Figs. 4 and 5 are perspective views, respectively, of the sheet-metal casin with tie thread-guard pin sustained there y and the tubular sto -member. Fig. 6 is a perspective view 0 one end portion of the controller-spring. Fig. 7 is a perspective view of the tension-stud.

The face-plate 1 is formed of sheet-metal of the usual arched-shape. It is formed at one side of its arched portion with an aperture entered by the central boss or stud 2 of the bushing 8 which is provided with a central bearin aperture 4. This aperture receives the re uced inner end portion 5 of the tension-stud having the screw-threaded and split outer portion 6 and the intermediate enlargement 7. The part 7 of the tension-stud has adjacent the portion 5 a boss 8 whose extremity ati'ords a spacing shoulder adapted to rest upon the face of the bushing 3, the arts 7 and 8 having therein a longitudinal groove 9.

The outer portion of the tension-stud has applied thereto the tension-disks 10 of well known construction, one of which has superposed thereon the arched washer 11 apertured to fit the exterior of the stud and provided with a cross-bar 12 passing through the slit of the portion 6 of the stud. Between said washer and the nut 13 applied to the threaded part of the outer end portion 6 is interposed the usual tensionspring 14.

Surrounding the bushing 3 and the body portion of the tension-stud is the cylindrical casing composed of a single strip of sheetmetal which is formed into a hollow cylinder 15 having at one side the integral 100 16 to afford a substantially cylindrical soc ret for the shank of the thread-guard pin. The opposite ends of the sheet-metal lank refera ly terminate in a slit 17 at a side 0 the body of the casing remote from the socket 16, the part 15 being formed at one end with a circular series of prongs 18 which enter a similar series of apertures in the face-plate concentric with the aperture 4, in which apertures they are secured by upsetting or riveting.

The socket 16 is entered by the straight portion of the thread-guard pin 19 having at its outer end the lateral segmental guardarm 20 extending beyond the tension disks and partially embracing the spring 14: in a well known manner. The pin 19 may be secured in its socket by the employment of a fusible bond, as in the use of a drop of solder to unite the parts or by the fusion of the parts to be united by the process of electric welding, which is deemed preferable: In either case, it is desirable to cause the opposite walls of the socket to firmly adhere to the pin so as to unite them together and secure rigidity of the casing on the side thereof at which the socket is formed.

Fitted to the inner wall of the casing 15 is the tubular stop-member 21 formed of a sheet-metal blank with its ends abuttcd to form the slit 22 adjacent which is formed Ill) in its outer end the notch 23 to afford a stop-shoulder 24. The member 21'is provided intermediate its ends with the threaded aperture 25 entered by the shank of the clamp-screw 26 passing throu ha segmental slot 27 in the casing'15 and a apted to secure the stop'member to the casing in circularly adjusted position to determine the location of the stop shotllder-Q-i. Surroundin the enlarged portion 7 of the tension-stu is the controller spring 28 having one end 29 bent at right angles with the adjacent coil substantially parallel with 1ts axis to enter the groove 9 above the boss 8, as represented in Fig. 1; the opposite end of said spring having a laterally extending arm 30 normally restin against the stopshoiflder 24 and provider with a thread-enga ing loop 81. The boss 8 serves to provi e an annular space for the end portion of the spring 28 adjacent the part 29-to prevent the crushing of the end ortion of the sprin and permit freedom or its adjustment y turning the tension-stud.

The bushing 3 is formed with a radial threaded aperture to receive the set-screw 32 passing through a round clearance aperture 325 of the casing and an elongated clearance aperture 34 of the relatively ad 'ustahle stop-member 21 and bearing upon the reduced portion 5 of the tension-stud. By loosening the set-screw 32, the tensionstud may be turned to wind up or unwind the controller-spring 28 and thereby vary the stress of the controller spring-arm 30 upon the thread leading from between the tension-disks without disturbin the adjustment of the stop-shoulder 24; w iile the stopmember 21 may be circularly adjusted relatively to the tension-stud and the surrounding casing by temporarily loosening the clamp-screw 26.

As represented in Fig. 1, the tension-stud is preferably of tabular form to receive the tension-releasing pin 35 whose outer end is adapted to'bear upon the cross-bar 12 of the was or 11, the opposite end being engaged by suitable means for relieving the pressure of the tension-spring when required.

While the resent improvement is shown and describe herein in the preferred form and arrangement of its component arts, it is obvious. that these may be modified to a certain extent without departure from the invention. "It is also obvious that the device is capable of ap lication to portions of the machine other tian the facelate without substantial alteration and sum application is within the scope of the invention.-

=Having thus set forth the-nature of'the invention, what I claim herein is 1.. In asewing machine, in combination, a support, a bushmg secured -to said support and provided with a bearing'a'perturem cylindrical casing secured to said support independentl of said bushing and concentrically wit 1 the bearing aperture ot the latter, a shouldered stop-member concentric with and fitted to one of the cylindrical faces of said casin a stud fitted to the bearing aperture of said bushing, a thread-controller spring SllllOllllClilW and having one end connected to said stud and provided at the other end with a lateralthread-arm resting against the shoulder of said stop-member, a. set-screw pendently of said bushing and concentrically with the bearing aperture of the latter and formed at one side thereof with a loop affording an adjacent .-integral socket, a shouldered stop-member concentric with and fitted to one of the cylindrical faces of said casing, a stud fitted to the'bearing aperture of said bushing. a thread-eontroller aprin; surrounding and having one end connected to said stud and provided at the other end with alateral threml-arm resting against the shoulder of said StOJ-fllClnllOl', a. set-screw accessible through said casing and entering the bushing for securing said stud adjustabl within the latter, a clamp-screw for securmg said stop-member adjustably to said casing, and a ri id thread-guard pin secured within said soc ct of the casing by a fusible metal bond.

3. -In a sewing machine, in combination, a support, a bushing secured to said support and provided with a bearing aperture, a cylindrical sheet-metal casing provided at one end with prongs entering and riveted within a ertures of said support concentrically wit 1 the bearing aperture of said bushing a shouldered sto -membcr concentric with and fitted'to one o the cylindrical. faces of said casing, a stud fitted to the bearing aperture ofsaid bushin a thread-controller sprin surrounding'anc having one end connecte to said stud and provided at the other end with a lateral thread-arm resting against the shoulder of said stop-member, a setscrew accessible through said casing and entering the bushing for securing said stud adjustably within the latter, and a clampscrew for securing said stop-member adjustably to said casing.

4. In a sewing machine, in combination, a sheet-metal face-plate formed with a circular series'of a ertures and with a central aperture, a bus iing formed with a bearing aperture and with a stud entering the central aperture of said face-plate in which it is secured, a cylindrical sheet-metal casing prowhich said casing is secured, a bus vided at one end with prongs entering the apertures of said circular series in the faceplate in which they are secured. a. tubular shouldered stop-member concentric with and fitted within said casing, means for securing it adyustably within said casin a stud fitted withm the bearing aperture of said bushing, means for securing it adjustably therein, and a thread-controller spring surrounding and having one end connected to said lastnamed stud and provided at the other end with a lateral thread-arm resting against the shoulder of said stop-member.

5. In a sewin machine slack-thread controller, the com ination with a stud and a controller-spring having at one end a connection therewith and at the other end a lateral thread-arm, of a cylindrical sheet-metal casing inclosing the spring, a fixed support to 1mg secured within said casing to said support and rovided with an axial bearing aperture or said stud, a set-screw a plied to said bushing for securing the stu adjustably in its bearing aperture a tubular stop-member fitted within said casin and surrounding said bushing and rovi ed with a shoulder for engagement with the lateral thread-arm of said spring, and a clamp-screw for securin said stop-member in circularly adjustab e pgsition upon said casing.

6. a sewing machine slack-thread controller the combination with a stud and a controller-spring having at one end a connection therewith and at the other end a lateral thread-arm, of a cylindrical sheet-metal casing inclosing the spring, a fixed support to which said casing is secured, a bushing secured within said casing to said support and provided with an axial bearing aperture for said stud, a set-screw applied to said bushing for securing the said stud adjustably in its bearing aperture, a sheet-metal stopmember fitted to a cylindrical wall of said casing for engagement with the lateral thread-arm of said s ring, and a clampscrew for securing sai stop-member in circularly adjustable position upon said casing.

7. In a slack-thread controller, a casing,

a support therefor, a shouldered stop-member mounted within and adjustably connected to said casing, a centrally apertured bushing secured to said support, a stud mounted for circular adjustment within said bushing a thread-controller spring secured at one end to said stud and havin a laterally extendin arm for engagin the t iread at its other end, and means for c ampiug said stud in circularly adjusted position whereby the tension of said thread-controller spring may be varied to suit the requirements 01fthe work.

In testimony whereof, I have signed my name to this specification.

JOHN D. KARLE.

Oooies of this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Washington, D. 0." 

